Michael Walzer is usually identified as one of the leading proponents of the "communitarian" position in political theory, along with Alasdair MacIntyre and Michael J. Sandel. Like Sandel and MacIntyre, Walzer is not completely comfortable with this label.[citation needed] However, he has long argued that political theory must be grounded in the traditions and culture of particular societies and opposed what he sees to be the excessive abstraction of political philosophy. His most important intellectual contributions include Just and Unjust Wars (1977), a revitalization of just war theory that insists on the importance of "ethics" in wartime while eschewing pacifism; the theory of "complex equality", which holds that the metric of just equality is not some single material or moral good, but rather that egalitarian justice demands that each good be distributed according to its social meaning, and that no good (like money or political power) be allowed to dominate or distort the distribution of goods in other spheres; and an argument that justice is primarily a moral standard within particular nations and societies, not one that can be developed in a universalized abstraction.

In On Toleration, he describes various examples of (and approaches to) toleration in various settings, including multinational empires such as Rome; nations in past and current-day international society; "consociations" such as Switzerland; nation-states such as France; and immigrant societies such as the United States. He concludes by describing a "post-modern" view, in which cultures within an immigrant nation have blended and inter-married to the extent that toleration becomes an intra-familial affair.[2]

In April 2008, Walzer received the prestigious Spinoza Lens, a bi-annual prize for ethics in the Netherlands. He has also been honoured with an emeritus professorship at the prestigious Institute for Advanced Study.

Walzer is married to Judith Borodovko Walzer. They are parents of two daughters: Sarah Esther Walzer (born 1961) and Rebecca Leah Walzer (born 1966). His grandchildren are Joseph and Katya Barrett, and Jules and Stefan Walzer-Goldfeld.